Here’s what happens when political bubbles collide

Social media has transformed how people talk to each other. But social media platforms are not shaping up to be the utopian spaces for human connection their founders hoped.

Instead, the internet has introduced phenomena that can influence national elections and maybe even threaten democracy.

Echo chambers or "bubbles" – in which people interact mainly with others who share their political views – arise from the way communities organize themselves online.

When the organization of a social network affects political discussion on a large scale, the consequences can be enormous....